1. Field of the Invention
The present invention relates generally to a method and system for managing a Push-To-Talk (PTT) over Cellular (PoC) box in a PoC system, and more particularly to a PoC box management method and system in which a PoC User Equipment (UE) stores in advance PoC box service parameters in a special server and a PoC box stores PoC media based on PoC box service parameter information of an associated PoC UE according to a session request in a multimedia PoC system.
2. Description of the Related Art
With the significant development of mobile communications and the broad extension of the communication network, various extended services and applications using mobile phones are being provided. According to various user requests, services beyond a simple call service is being such as positioning, multimedia and Push-To-Talk (PTT) services, are being provided. Specifically, the PTT service supports various additional functions such as instant messenger and state display, as well as a group call and a voice call that are possible in a conventional radio system or a Trunked Radio System (TRS).
A concept of this PTT service is being actively discussed to standardize a PTT over Cellular (PoC) service using a mobile communication network. One characteristic of the PoC service different from the conventional mobile communication service is that users can perform communication while moving between multiple sessions according to need. The requirement that users should be able to perform communication while moving between multiple sessions is prescribed in the standard of the Open Mobile Alliance (OMA) serving as an organization for developing a standard for a mobile communication service.
As defined in the PoC 1.0 standard, media data is sent only to PoC clients participating in a PoC session in real time. Thus, users who do not participate in the PoC session due to reasons such as battery discharge and absence, cannot receive a media stream such as voice in a 1-1 or group PoC session. That is, the PoC 1.0 technology does not support a function of a voice mailbox supported in the conventional Circuit Switched (CS) communication.
To address the problem when a PoC UE does not participate in the session and cannot receive a media stream, OMA PoC Release 2 considers a PoC box for which the function is similar to that of a Multi Media (MM) box for a conventional Multi Media Service (MMS). In a PoC box service, a PoC client incapable of participating in a 1-1 or group PoC session in real time participates in the associated PoC session using a particular physical or logical storage system. As described above, the PoC box stores media sent in the session when the PoC client participates in the associated PoC session. Subsequently, the stored media are provided and reproduced according to the PoC user's request.
A conventional method employs a Session Initiation Protocol (SIP) PUBLISH message to implement a PoC box service, in which, a PoC box service request is sent to a PoC server using the SIP PUBLISH method. When the request is made, a type of media to be stored in the PoC box is directly contained in an SIP request message to be transmitted to the PoC server. This technology requires an extension of an Extensible Markup Language (XML) schema format for defining PoC service setting values in the PoC 1.0 standard, an XML document is directly stored in the PoC server. An XML document can be dynamically accessed, edited, and modified independent of an SIP message. Because multiple PoC service setting values are stored when PoC box service related data is directly stored in the PoC server, the load of the PoC server can increase and various XML documents relating to the PoC service cannot be managed in an integrated manner.